The health and dietary information of more than 3,000 subjects aged 55 to 80 years old were studied for nearly 10 years (mean) in the Age-Related Eye Disease Study (AREDS). They filled out questionnaires at the beginning of the study and lens photographs were taken each year. As the study progressed researchers assessed whether the patients had cataract surgery, and whether and how severe instances of cataracts occurred.

At the start of the study it was noted that where the diet included greater amounts of these nutrients the incidence of cataract was less, an inverse relationship. And as the study continued it was noted that these relationships continued - the greater the levels of the B vitamins mentioned, the less occurance and severity of cataract.

To be more specific, highest levels of B6 in the diet were associated with decreased risk of moderate lens opacity. Highest dietary levels of B3 and B12 were tied to decreased risk of mild cataracts in patients who were not taking multivitamins. However, for patients taking multi-vitamins, the highest intake of folate was associated with increased risk of mild lens opacity. There were no statistically significant associations between lutein plus zeaxanthin and cataract development.